Twitter said in a November regulatory filing that it received a letter from IBM accusing it of infringing on three of its patents. The letter asked Twitter to take part in settlement negotiations, but Twitter said at that time that it believed it could defend itself against the allegations.

As a relatively new company. San Francisco-based Twitter holds just a handful of patents. Meanwhile, Armonk, N.Y.-based IBM Corp. holds more than 41,000 and received a total of 6,809 last year.